Benefits of Trees for Human Health + Forest Bathing

Jason Henning, research urban forester for Davey Tree, discusses the human health benefits of trees and why it's important to spend time in nature and around trees.

We're celebrating Arbor Day all month long with the Davey Planting Project Giveaway! We want to promote tree planting this Arbor Day, so we're giving away tree seeds to anyone and everyone who is interested! All you have to do is email a mailing address to podcasts@davey.com and you'll receive your complimentary seeds in the mail along with planting instructions.  You have until the end of the month to send us an email for your seeds. *Seeds can only be mailed within the U.S.

In this episode we cover:

• Forest bathing (1:15) (15:31)
• Health benefits of being in nature (2:17)
• Small forests in urban areas (3:40 )
• iTree (4:47)
• How Jason started his job (5:45)
• Urban forestry (7:43)
• Best trees for urban environments and tree diversity (9:45)

To find your local Davey office, check out our find a local office page to search by zip code.

To learn more about tree benefits, read our blog, Benefits of Planting Trees - Latest Research.
To learn more about tree benefits such as shade and why it's important for our health, read our blog, The Benefits of Shade Trees - Nature's Sunscreen.
To learn more about i-Tree and how it can be used, read our blog, i-Tree Tools Help You Better Know Your Trees and Their Benefits. 

Connect with Davey Tree on social media:
Twitter: @DaveyTree
Facebook: @DaveyTree
Instagram: @daveytree
YouTube: The Davey Tree Expert Company
LinkedIn: The Davey Tree Expert Company

Transcript

[music]

Doug Oster: Welcome to the Davey Tree Expert Company podcast Talking Trees. I'm your host Doug Oster. Each episode showcases one of Davey's certified arborist sharing advice with everyone about caring for your trees and landscapes. We'll talk about everything from introduced pest, seasonal tree care, deer damage, how to make your trees thrive, and much much more. Tune in every Thursday to learn more because here at the Talking Trees podcast, we know trees are the answer. Welcome back tree and nature lovers, before we talk forest bathing, don't forget to send for your free tree seeds as part of the Davey planting project in celebration of Arbor Day.

All you need to do is send an email requesting the seeds to this address. It's podcasts, that's plural, @davey.com. Let me spell that, podcasts@davey.com. We'll get those seeds right out to you. For our third week of our celebration of Arbor Day welcoming Jason Henning, research urban forester for the Davey Institute to the show. How are you, Jason?

Jason Henning: I'm good, Doug.

Doug: Today's topic is all about forest bathing. That's a new term for me. It just sounds to me like running around in the woods when I was a kid. How much I enjoyed time with the trees. How do you interpret forest bathing?

Jason: I think I probably come down the same place you do. I know that there's really a technical definition. It comes from almost a little bit of spiritual background but maybe that's all where we get started when we wander in the woods anyway. I guess I don't think about it that way but anytime in the woods or outside for me, counts.

Doug: Did you spend a lot of time in the woods as a kid?

Jason: Oh, yes, I spent a lot of time in the woods. We had small patches of woods near our house, we build forts, dig big holes, try and trap animals that probably weren't there. All that stuff.

Doug: Now, that's forest bathing.

[laughter]

Doug: Let's just talk about the benefits of being out in nature, being out in the forest. I think everybody knows that it's wonderful feeling to spend time out there in the quiet.

Jason: Sure, sure. I mentioned the kind of the forest bathing in a real historical way it's been thought of. Comes from a little bit of a spiritual meditation background, but there's a whole bunch of science on the other side in recent years that show all sorts of benefits just being around green things, maybe it's in the forest proper, maybe it's just being able to see green out your window. There's all sorts of stuff around reducing stress, and cortisol levels, and all sorts of really technical scientific stuff.

We've done some research with the US Forest Service folks around green space and reducing crime. Then there's just benefits around trees removing air pollution. Anytime we can breathe cleaner air that's going to have some benefits for us, too. There's really a growing body of research where the science meets the spiritual, it seems like if that's the way we can go make everybody happy, then we should do it.

Doug: You mentioned small forest. Let's talk a little bit about that.

Jason: Sure. We've been doing some work just looking around since we know that trees have benefits and forests have benefits. The idea is, how do we get people to those benefits? We did some work to see how forests are distributed on the landscape, especially where they connect with people. We're talking about urban areas, we're getting more and more people living in urban areas. Here on the East Coast, between the I-95 corridor from DC up to Boston, we looked at just what are the size patches of forest that most people have available. We think about big national forests and big parks, but what we found there was about half of the people their nearest forest is six acres or smaller.

Most of what we have is really small patches around these urban areas, but they provide all the same benefits. You can still get in there and be surrounded by green and be in nature and get some of those benefits around reduced stress levels and all things like that.

Doug: What about something called i-Tree that you told me about before we came on?

Jason: Sure. A lot of the work we do, I mentioned this with those small patches is we want to get to how do we relate where the trees are and how many trees we have so that we can make them of benefit to the most people. One of the tools we have that we work on with the US Forest Service, it's actually a suite of tools called i-Tree. Anybody can go in there. We have a website, itreetools.org. You can put in trees around your house, and you can estimate the benefits that they're providing to you. Things like air pollution removal, maybe they help you reduce your heating and cooling costs, that has some stress-relieving aspects to it too.

All things along those lines. You can estimate with these i-Tree tools and get an idea of the benefits of trees, especially close to where you live in particular.

Doug: I saw an email we sent back and forth to each other that you are the first Ph.D. that I have interviewed on the podcast, tell me how you got interested in this as your way to make a living?

Jason: Sure, sure. We talked a little bit how I like to spend time outside. As a kid, when I first started in school, I didn't really know what I wanted to do but I figured, I like outside, I like trees more than people. I would move towards that kind of thing. I got a degree in natural resource management but I had an advisor who decided that I was good at math. He set me on a path to start doing some grad work. I moved around to a couple different places and actually got my Ph.D. in a subset of forestry called forest biometrics, which is real math and statistics heavy. I was as far away from people as possible, with that focus.

Really out there in the woods, measuring trees, and measuring how much timber we were producing and things like that. Then I had an opportunity to move back close to home. I was down in Tennessee, and had an opportunity to move back actually back into the city of Philadelphia and I grew up near there, and my family's here. It was this urban forest research position. It was a great opportunity for me. Now, my concern is so much more around people and how we get them close to the trees rather than just worrying about the trees and avoiding the people. It's been good for me for sure. It's super fun to see all different folks connect with trees and the benefits they provide.

Doug: What else can we talk about regarding urban forestry? Because that really sounds interesting to me. We started with thinking that people in the city in these certain areas you were studying could find six acres of forest. To me, that sounds like a lot of forest in the city. Of course, me living out, away from the city, six acres is nothing. What else have you learned about urban forestry?

Jason: Sure. Urban forestry it hasn't been around nearly as long as traditional forestry. Really when we talk about urban forest, we're talking about all the trees in the city. These can be just street trees, or even really small patches. Some of the really cool stuff that we've found and that researchers, where I work in Philadelphia found that taking vacant lots and turning them into green spaces with a tree or two, and a fence and some grass really has a lot of those benefits that we talked about with forest bathing. They've done things like put heart rate monitors on folks and had them walk by vacant lots that have been cleaned up in green.

Then by what you would more typically consider vacant lot and just those tiny pieces of forest are enough to lower heart rates, lower cortisol levels, and that sort of thing. We talk about forests and if you're really out in the forest, you may not think of street trees as part of your forest. If you're in a city, those street trees are really doing a lot of the work. There are hundreds of people passing under them every day enjoying the shade and the green space. Urban forests become a really interesting place to work when you start to think about how they interact with the people who are there and all different pieces of those urban forests from natural spaces to just a single street tree you have front of the house.

Doug: When you're thinking about adding trees in an urban environment. What are some of your favorite types to put in? What do we have to think about? Does it have to be super tough or can it be a tree we'd grow out 10 miles from the city?

Jason: That's an interesting question. Even within a city, there's tons and tons of variability. If you're looking at a street tree, they've got those really small pits that might be 6 feet by 6 feet or 8 feet by 8 feet. You're going to need something tough there because there's going to be snowplows piling snow up there and salt and all the air pollution from the car. You are going to need something tough in those situations. There's been enough research around that that we've got a lot of tougher trees and they're doing great work putting them out there and still having them be interesting on the landscape, but able to survive under city conditions.

If you've got a nice open yard, there's no reason not to plant a big red oak or something that can get really big like that because that's another thing that we know is that the bigger stature trees are going to provide you with more benefits. They're going to provide you with more shade and more green space so you plant those big trees where you have opportunity, but where you don't, we really do have some options for some tough trees they don't make it out there.

Doug: Let's say that you're standing there on the street and you're looking at this pit with a bunch of other people and you know that that snowplow is going to be throwing salt and stuff on it and you look at each other and say, "What are we going to plant here?" What can you plant there?

Jason: I think there's been a lot of work on that and they're always trying to get more diversity. Always thinking in that way is really good. If you think back to things like Dutch elm disease, where we had beautiful boulevards with elms on both sides. Dutch elm disease came through, you had no trees and it's the same thing with emerald ash borer. We've lost huge street trees. Variety is always good, but we see lots of things like honey locust these days. They're being real intentional about planting smaller trees especially under wires and things like that, where it's appropriate.

They're still old favorites like the London plane is still one of the most popular trees. Any big city you go to you're going to find London planes, and it's because they are so tough. They can survive and thrive in those urban situations. Then there's also cool research even I mentioned the elms before, but they are hybrid elms that they're starting to try and plant in cities and in tree pits, street tree pits specifically. Some of that stuff may come back as well as we move forward here in the next couple decades.

Doug: That's a really interesting point that you made about diversity because for all those years, it was standard practice. We want a row of the same thing down the road everywhere. It's got to look the same, but now we don't want that. You're saying we want diversity and when you bring up honey locust, it's interesting because for somebody like me who grew up with a honey locust at the edge of the driveway, I just remember sitting underneath that thing and watching the bees do their thing on the tree and just the smell of it. I love a honey locust, but not everybody does. Everybody has their own favorite trees.

Jason: That's almost something we can take advantage of. If you talk about diversity, if everybody's got their own different favorite tree maybe that's where we can go because lots of times cities will put out these tree lists of suggested trees and it's tough for folks to picture what those are, but if you've got a favorite tree already and it works for your location, that can be a great way to go.

I know here in Lancaster, we've actually got a really cool spot where the city arborist planted all the street trees that they recommended in just a little plot. You can go by and you can look at all of them side by side and say, "Oh yeah, I'm not a tree expert, but I recognize that little bald cypress or whatever it happens to be there. I'd like to see something like that on my street." It's a really cool spot.

I like walking around there even though I know all the trees, it's just cool to see them all side by side. Another thing that I think is really cool is that there's more interest in planting actual fruit and nut-bearing trees in cities. There was a lot of worry that they make a big mess, but people really like them. If there's one on your block and it just becomes something that people are interested in and again, it gets people tied into the ideas of trees and the benefits they provide and trees in urban spaces.

Doug: I love that idea of being able to see the trees. When you're in that area, are you ever there when people are just looking around and saying, "What's this? What's that? Or I like this, I like that," and then you can jump in like superman. That happens to be a--

Jason: That's what I hope, but no, I haven't actually seen anybody quite as interested as I am but I'll keep hanging out there and we'll see if anybody else shows up.

Doug: Let's get back to forest bathing, how we interpret forest bathing. Like you said, technically is it going out into the woods and actually sitting there and actually doing meditation, or can forest bathing be accomplished by just walking a trail through a forest? What do you think?

Jason: I think it can be accomplished with some flexibility, for sure. There are benefits to going out there and being quiet and meditating, but I think there's benefits to all of it. Anytime you can get outside is good. If you can get outside with maybe just a little more mindfulness or attention especially if it's a place you go to all the time, you can really pay attention to how it changes through the seasons or something like that. Even just that kind of little thing can help you calm down and stop thinking about all the other stuff we have going on all the time. I think you can definitely get outside any way you can. If you can remember to take a deep breath, I think you're definitely helping yourself.

Doug: Well, Jason, that is great advice. That's where we're going to leave it today. Thanks again for all the wonderful information. I learned a lot today. Thanks again.

Jason: Great to talk to you, Doug.

Doug: Tune in every Thursday to the Talking Trees podcast from The Davey Tree Expert Company. I'm your host Doug Oster. Next week we'll continue our monthlong celebration of Arbor Day with some great stories, interesting interviews, including an important Earth Day episode revolving around environmental justice. Don't forget to email podcasts, that's plural, @davey.com. podcasts@davey.com for your free tree seeds as part of the Davey planting project. You've got until April 30th and we'll send those seeds right out to you. As always on the Talking Trees podcast, we know the trees are the answer.

[00:17:36] [END OF AUDIO]